// Copyright 2021 Datafuse Labs
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

pub fn defer<F: FnOnce() -> R, R>(f: F) -> impl Drop {
    struct Defer<F: FnOnce() -> R, R>(Option<F>);

    impl<F: FnOnce() -> R, R> Drop for Defer<F, R> {
        fn drop(&mut self) {
            self.0.take().unwrap()();
        }
    }

    Defer(Some(f))
}
